A conventional connector structure for cleaners is usually connected to a water faucet with screw bolts, and is pushed to contact the water faucet with the force generated by the screw bolts. These screw bolts have to be precisely aligned to achieve accurate positioning and a poor alignment likely causes a water leak. To solve this problem of the conventional connector structure, the inventor has previously invented a fast connector structure for cleaners as illustrated in FIGS. 9 to 11. The fast connector structure of the previous invention comprises a water pipe 60 and a fast connector 70, wherein one end of the fast connector 70 is connected to the water inlet end 61 of the water pipe 60, and the other end of the fast connector 70 is molded with thread 701 which allows it to be placed into the screw hole of the water outlet of the faucet 80. The fast connector 70 has a horizontal slot 703 located in the middle portion of the water hole 702, and the horizontal slot 703 has on one end a closed position limiting stopper 704, and on the other end an opening 705 through the side wall of the fast connector 70. The opening 705 is expanded downwardly and allows the interposition of a positioning piece 71, which has in its center a through slot 711 with a size larger than the water hole 72 and an inner side edge 714 at the inner end of the positioning piece 71. In addition, the positioning piece 71 has a push button 712 located at the end that protrudes out from the horizontal slot 703, and there is a spring 72 placed between the inner side of the lower part of the push button 712 and the wall of the opening 705 which maintains the positioning piece 71 to be pushed outwardly. In addition, the positioning piece 71 has two horizontally extended portions 713 located at the inner ends of both its left and right borders, which are to be placed into the recessed portions 706 of the horizontal slot 703, and the recessed portions 706 of the horizontal slot therefore prevent the positioning piece 70 to slide out from the horizontal slot 703. Furthermore, the bottom end of the water hole 72 of the fast connector 70 is formed into a reamed zone 707 which is installed with a spring 73, and the water inlet end 61 of the water pipe 60 has a recessed ring slot 62, therefore when the water inlet end 61 of the water pipe 60 is inserted into the water hole 702 of the fast connector 70, the recessed ring slot 62 is placed at a position that fits the horizontal slot 711 of the positioning piece 71. As the positioning piece 71 is elastically pushed outwardly, the inner side edge 714 of the horizontal slot 711 is then interposed into the recessed ring slot 62 of the water inlet end 61, thereby achieving the proper positioning of the water inlet end 61 of the water pipe 60 and preventing the detachment of the water pipe 60 from the fast connector 70.
However, for the previously invented fast connector structure as above described, the inner side edge 714 of the positioning piece 71 blocks the recessed ring slot 62 at only one side and does not provides a full circle stabilization to the recessed ring slot 62 of water inlet end 61; therefore the contacting area as well as the positioning limiting strength are limited, which likely results in the detachment of the water pipe 60 from the fast connector 70 due to high water pressure and causes a dramatically reduced convenience in practical uses.
Therefore, there remains a need for a new and improved fast connector structure to overcome the problems stated above.